This invention relates generally to methods and systems for remediating contaminated soil or water and, more particularly, to a gravity induced soil remediation system for filtering dissolved solid waste material from a waste stream.
Over time, soil and associated ground water areas may become contaminated with solvents, agricultural chemicals like pesticides, industrial waste, agricultural chemicals, or other waste that is not properly disposed of. The most common soil pollutants are The most common chemicals involved are petroleum hydrocarbons, polynuclear aromatic hydrocarbons (such as naphthalene and benzopyrene), solvents, pesticides, lead, and other heavy metals. A significant problem with soil contamination has been experienced around airports where propylene glycol is used in significant amounts to de-ice airplanes at commercial airports. Propylene glycol runs off into the soil from the areas where airplanes loaded with passengers are de-iced prior to flight. The propylene glycol in the soil and water may be referred to as a waste stream and can cause health problems, destruction of property, and damage to the character and quality of the soil.
Various systems and methods have been used in the past to remediate soil or to otherwise filter or purge dissolved waste material from a water stream. For instance, large volumes of contaminated soil or water streams may be removed from an area and replaced with uncontaminated soil. In other cases, the contaminated soil may be flushed with large volumes of water under high pressure or treated with other chemicals so as reduce the effect of undesirable pollutants. In addition, activated carbon is effective in filtering pollutants from polluted air and water streams and, therefore, is frequently employed in water filtration systems and in soil remediation. However, the carbon media requires moderate to high pressure to become activated to absorb pollutants. This method may require pumps or other means to create pressure upon the carbon filter media in order to activate the carbon media to act upon the contaminants.
Although presumably effective to achieve the intended results, the existing methods for remediating contaminated soil or water are expensive, require undesirable logistics of excavating and transporting contaminated soil, or require a means for introducing pressure to activate the filtration media.
Therefore, it would be desirable to have a gravity induced soil remediation system for filtering dissolved solid waste material from a liquid waste stream. Further, it would be desirable to have a gravity induced soil remediation system having a series of trench members that each include filter media for cleaning a waste stream, each trench member being situated at a lower elevation than a previous trench member so that portions of the waste stream are moved downwardly into contact with carbon filter media by gravity rather than by a pump.